body {
    background: linear-gradient(135deg, #e9eff5 0%, #e9eff5 100%); /* Subtle gradient background */
    color: #333;
    font-family: 'Open Sans', sans-serif; /* Use a more modern font */
}

.advanced-search-container {
    background: white;
    padding: 2rem;
    border-radius: 0.5rem;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1); /* More pronounced shadow for depth */
    margin-top: 2rem;
    margin-bottom: 2rem;
}

h2 {
    text-align: center;
    color: #007bff; /* Theme color for headings */
    margin-bottom: 1.5rem;
    font-weight: 300;
}

hr {
    border-top: 1px solid #dee2e6;
    margin-bottom: 1.5rem;
}

.form-row {
    margin-bottom: 1rem;
}

.col-form-label {
    text-align: left;
    font-weight: 600; /* Slightly bolder labels for better readability */
    color: #007bff; /* Theme color for text */
}

.btn {
    background-color: #007bff; /* Primary button color */
    color: white;
    border-radius: 30px; /* More rounded corners for buttons */
    padding: 0.75rem 2rem;
    font-weight: bold;
    border: none;
    transition: all 0.2s ease; /* Smooth transition for interactions */
}

.btn:hover,
.btn:focus {
    background-color: #005ecb; /* Slightly darker shade on hover/focus */
    box-shadow: 0 0 0 0.2rem rgba(0,123,255,.5); /* Glow effect on focus */
}

.form-control {
    border-radius: 30px; /* More rounded corners for input fields */
    transition: border-color 0.2s ease-in-out; /* Smooth transition for focus */
}

.form-control:focus {
    border-color: #007bff; /* Highlight color */
    box-shadow: 0 0 0 0.2rem rgba(0,123,255,.25);
}

.form-group {
    margin-bottom: 1rem; /* Consistent margin for form groups */
}

/* Responsive adjustments */
@media (max-width: 768px) {
    h2 {
        font-size: 24px;
    }

    .advanced-search-container {
        padding: 1rem;
    }

    .btn,
    .form-control {
        padding: 0.5rem 1rem;
    }

    .input-group {
        flex-direction: column;
    }
}